func Clone[T any](s T) T {
	return runtime_arena_heapify(s).(T)
}

//go:linkname reflect_arena_New reflect.arena_New
func reflect_arena_New(a *Arena, typ any) any {
	return runtime_arena_arena_New(a.a, typ)
}

//go:linkname runtime_arena_newArena
func runtime_arena_newArena() unsafe.Pointer

//go:linkname runtime_arena_arena_New
func runtime_arena_arena_New(arena unsafe.Pointer, typ any) any

// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package cgotest

import _ "unsafe"

//go:linkname lockedOSThread runtime.lockedOSThread
//extern runtime_lockedOSThread

		}
		if got, want := h2.Gname, v.h.Gname; got != want {
			t.Errorf("i=%d: Gname: got %q, want %q", i, got, want)
		}
		if got, want := h2.Linkname, v.h.Linkname; got != want {
			t.Errorf("i=%d: Linkname: got %v, want %v", i, got, want)
		}
		if got, want := h2.Typeflag, v.h.Typeflag; got != want {
			t.Logf("%#v %#v", v.h, fi.Sys())
			t.Errorf("i=%d: Typeflag: got %q, want %q", i, got, want)

	// Use long-link files if Name or Linkname exceeds the field size.
	const longName = "././@LongLink"
	if len(hdr.Name) > nameSize {
		data := hdr.Name + "\x00"
		if err := tw.writeRawFile(longName, data, TypeGNULongName, FormatGNU); err != nil {
			return err
		}
	}
	if len(hdr.Linkname) > nameSize {
		data := hdr.Linkname + "\x00"

//
//	                  |  USTAR |       PAX |       GNU
//	------------------+--------+-----------+----------
//	Name              |   256B | unlimited | unlimited
//	Linkname          |   100B | unlimited | unlimited
//	Size              | uint33 | unlimited |    uint89
//	Mode              | uint21 |    uint21 |    uint57
//	Uid/Gid           | uint21 | unlimited |    uint57

	// Create an archive with a large linkname
	fileinfo, err := os.Stat("testdata/small.txt")
	if err != nil {
		t.Fatal(err)
	}
	hdr, err := FileInfoHeader(fileinfo, "")
	if err != nil {
		t.Fatalf("os.Stat:1 %v", err)
	}
	hdr.Typeflag = TypeSymlink
	// Force a PAX long linkname to be written
	longLinkname := strings.Repeat("1234567890/1234567890", 10)
	hdr.Linkname = longLinkname

	hdr.Size = 0

		}
	}

	// Check basic fields.
	var blk block
	v7 := blk.toV7()
	ustar := blk.toUSTAR()
	gnu := blk.toGNU()
	verifyString(h.Name, len(v7.name()), "Name", paxPath)
	verifyString(h.Linkname, len(v7.linkName()), "Linkname", paxLinkpath)
	verifyString(h.Uname, len(ustar.userName()), "Uname", paxUname)
	verifyString(h.Gname, len(ustar.groupName()), "Gname", paxGname)
	verifyNumeric(h.Mode, len(v7.mode()), "Mode", paxNone)

	}

	var p parser
	hdr := new(Header)

	// Unpack the V7 header.
	v7 := tr.blk.toV7()
	hdr.Typeflag = v7.typeFlag()[0]
	hdr.Name = p.parseString(v7.name())
	hdr.Linkname = p.parseString(v7.linkName())
	hdr.Size = p.parseNumeric(v7.size())
	hdr.Mode = p.parseNumeric(v7.mode())
	hdr.Uid = int(p.parseNumeric(v7.uid()))
	hdr.Gid = int(p.parseNumeric(v7.gid()))

			ModTime:  time.Unix(1392395740, 0),
			Typeflag: 0x53,
			Linkname: "",
			Uname:    "david",
			Gname:    "david",
			Devmajor: 0,
			Devminor: 0,
			Format:   FormatGNU,
		}, {
			Name:     "sparse-posix-0.0",
			Mode:     420,
			Uid:      1000,
			Gid:      1000,
			Size:     200,
			ModTime:  time.Unix(1392342187, 0),
			Typeflag: 0x30,
			Linkname: "",
			Uname:    "david",
			Gname:    "david",

to make a switch from the Go runtime world to the system C (GCC-based)
world.

For example, here is the definition of _Cfunc_puts:

	//go:cgo_import_static _cgo_be59f0f25121_Cfunc_puts
	//go:linkname __cgofn__cgo_be59f0f25121_Cfunc_puts _cgo_be59f0f25121_Cfunc_puts
	var __cgofn__cgo_be59f0f25121_Cfunc_puts byte
	var _cgo_be59f0f25121_Cfunc_puts = unsafe.Pointer(&__cgofn__cgo_be59f0f25121_Cfunc_puts)